Mixing oil weights

I was wondering how would mixing 3 gts 20-50 of the same brand oil with 4 qts of 5-30 oil change the viscosity if the total blend. I have a 2011 5.7 hemi in a ram 1500 truck with 65k miled and I had to replace the cam, lifters, oil pump, Vvt valve and phaser. Now at startup it has the "hemi tick". I've never had that before and those 2 -3 seconds of tick drives me crazy each morning.
Rod